Kick starter



y 13, 1952 F. s. THOMAS, JR 2,596,512

" KICK STARTER Filed April 30, 1948 2 SHEETSSHEET l HvroeMgrlg,

FRHNK 5. THaMAgJQ.

May 13, 1952 F. s. THOMAS, JR

KICK STARTER 2 SHEETS-SHEET 2 Filed April 30,. 1948 w I f Ill/(1 1111111,

Patented May 13, 1952 UNITED STATES PATENT OFFICE KICK STARTER Frank S. Thomas, Jr., St. Louis, Mo., assignor to Development Corporation, Inc., St. Louis, Mo., a corporation of Missouri Application April 30, 1948, Serial No. 24,352

6 Claims. 1

The present invention relates generally to starter constructions, and more particularly to a kick starter mechanism for a motor.

An object of the present invention is to provide a novel kick starter for a motor which is positive in action in its starting phase.

Another object is to provide a novel kick starter for a gasoline motor, or the like, in which a movable gear segment positively engages a gear or pinion during the starting phase and is kicked free of the gear or pinion thereby upon starting prior to disengagement, in which such movable gear segment is thrown free of its gear engaging position by centrifugal force during normal fast return of the starting device to original rest position, and in which such movable gear segment rides lightly on the energized motor gear during slow return of the starting device to rest.

Another object is to provide a novel kick starter for a motor which includes relatively movable elements which are maintained in nonchatter relation when in the rest positions thereof.

Another object is to provide a novel kick starter for a motor which includes a movable gear segment which is biased into motor pinion engagement by the drag of the engine on the pinion.

Another object is to provide a novel kick starter for gasoline motors, or the like, which is constructed to prevent damaging clash of a gear segment in its return from started to starting position.

Other objects are to provide a novel kick starter for gasoline motors, and the like, which is sturdy in construction, which is efficient in operation, which is adapted to remain in operative condition for extended periods of time without maintenance, which is inexpensive and which is both simple in construction and in operation.

The foregoing and other objects and advantages are apparent from the following descrip tion taken with the accompanying drawings, in which:

Fig. l is a side elevational view of a gasoline motor suspended from the frame of a bicycle showing a kick starter operatively connected therewith which is constructed in accordance with the teachings of the present invention, only a fragment of the riser, vertical and horizontal bars of the bicycle being illustrated, the starter being shown in rest position;

Fig. 2 is a view similar to Fig. l, with the starter shown in motor pinion engaging position;

Fig. 3 is a view similar to Fig. 1, with the starter 2 in extreme position of movement and beyond engagement with the pinion;

Fig. 4 is a view similar to Fig. 1, but showing the position of the several parts of the starter during the fast returning movement thereof;

Fig. 5 is an enlarged fragmentary plan view of the starter elements and immediately associated parts as they appear in Fig. 2;

Fig. 6 is an enlarged vertical transverse view on substantially the line 6--6 of Fig. 2 through the starter elements and parts of the motor unit;

Fig. 7 is an enlarged vertical transverse crosssectional view on substantially the line 1---'! of Fig. 2;

Fig. 8 is an enlarged cross-sectional view on substantially the line 8-8 of Fig. 1;

Fig. 9 is a side elevational view of the starter bell crank and movable gear segment; and

Fig. 10 is a view of a fragment of the starter bell crank.

Referring to the drawings more particularly by reference numerals, l5 indicates generally a kick starter constructed in accordance with the teachings of the present invention, which is shown applied to a one-cylinder motor unit [6 suspended from the pedal crank housing of a bicycle, only fragments of the riser bar l8, vertical bar l9 and horizontal bars 20 being shown.

The motor I6 includes a crankcase 22 in the walls of which is journaled a crankshaft 23. On one end of the crankshaft 23 is a flywheel 24 and on the other end a clutch construction 25 and a pinion or small gear 26. l

The kick starter I5 includes a bell crank 32 comprising an arm 33 terminating in a foot pedal portion 34 and a forked arm 35 connected by an arcuate portion 36 at the extremities thereof. Spaced slots 31 are formed in the arcuate portion 36, and are positioned as extensions of chords of circles centered at the juncture of the arms 33 and 35, as is clearly shown in the drawings, particularly in Figs. 9 and 10. At the juncture of the arms 33 and 35, the bell crank 32 is formed with a bearing hub 40 (Fig. 7). The bearing hub 40 is disposed on a stub shaft 4| threadedly mounted in a threaded aperture 42 in the crankcase 22, and is maintained in position thereon by a washer 43 and a nut 44 secured on a reduced threaded extension 45 of the stub shaft 4|. A relatively heavy coil spring 41 is disposed about the bearing hub 40, one end of which is secured to a post 48 threadedly mounted in the crankcase 22, and the other end of which is hooked at 49 and extends through an opening 50 in the bell crank 32. The spring 41 biases the bell crank 32 clockwise to the position shown in r Fig. 1.

A gear segment 55 is mounted adjacent one side of the arcuate portion 36 by means of rivets 56 which are anchored in the gear segment 55 and extend into the slots 3'! of the portion 35 (Figs. 8 and 9). As is clear from Fig. 8, the gear segment 55 has sufiicient play in respect to the portion 35 to permit ready relative movement thereon. The gear segment 55 includes arcuately disposed gear teeth 58 and an integral stop lug t.

The stop lug 59 engages a rod 60 mounted in the" crankcase 22 when the bell crank 32 is in its po sition of rest (Fig. 1).

7 Operation The kick starter I5 is normallyin the position of rest shown in Fig. 1. Its substantially extreme position of movement is shown in Fig. 3, intermediate positions being shown in Figs. 2 and 4.

Assumingthat the motor .unit it is notoperating and it is desired to start the same, thefoct of an operatorisplaced on the foot portion 36 of thebell crank 32;and the bell crank 32 is pivgear segment 55;is,rotated into predetermined engaging relation with the teeth of the pinion 28.

Duegto' the positioniof the slots 31, the dragging action of the gearsegment 58 through pull by counterclockwiserotation of the bell crank 32 forces the-gearis-egment55 to the bottom'of the slots. 3fl.w Anydraggor-resistance on the part of the pinion 26 only snugly draws the gear segment V 55 intoits lowermost position, which is one which permits-the necessary,clearancebetween its teeth andjthef teeth-ofthei-pinion 56.to permit rotation of the latter by'theLformer'. However, should the motor: I6:fire:.whilesthe gear segment 55 is in engagement; with: the; pinion.v 25,: the accelerated counterclockwise:rotation; .of ,thetpinion will throwthe:gear:segment;5.5ito a raised position and, onein whichdtszteethjli; arefree from the teeth r of the gear-126;.

The belllcranki32;is;returned;from the position of Fig; 3 tor-its rest-position ofFig 1 by the spring 41. The movement is sufiiciently rapid-to move the'gearv segment 55.,outwardly to some such position.as;that:sho.wn: inFig; 4 under the effects of centrifugalforce. Hence, in the return of the bell. crank 32 toits positionof rest, there is no engagement between the teeth. 58 of the gear segment :,and thevteethfofvthe, pinion 25. Howkick starter which .fulfills the objects and advantages sought therefor.

It is to be understood that the foregoing description and the accompanying drawing have been given by way of illustration and example. It is also to be understood that changes in form of the elements, rearrangement of parts, and substitution'of equivalent elements, which will be obvious to those skilled in the art, are contemplated as within the scope of the present invention, which is limited only by the claims which follow.

Whatiis claimed is:

1. A starting device, comprising a bell crank levenpivotally mounted for movement between a first position-and a second position; pinion rotating means mounted on one arm of said bell crank lever 'for limited movement in a predetermined direction relative thereto; and 'means guiding the movement of the" pinion rotating means relative to the bell crank lever, said-pinion rotating. means having .free and unencumbered limited movement-relative to said one arm except for that caused by contact withthe guidin uneans. i

2. A starting device, comprising abell crank lever pivotally mounted for movement between a starting-position and a finish position; pin-ion rotating means mounted on one arm of saidl bell. crank lever for limited radial and transverse movement relative. thereto; and means guiding the movement ofthe pinion rotating means relative to=the bell crankalevensaid pinion-rotating: means having free and unencumbered limited 1 radial and transverse movement relative. to saidr one arm except for that caused by contact with. the. guiding means, the; guiding; means. being pcsitionedso'the pinion rotating means ismoved; backwardly and outwardly relative to saidone arm when the bell'crankilever'is pivoted fromqt'nea V finish position tonthe'.startingiposition;

ever, should thereturn movement be slow enough I to permitlthe"gear-segment 55 .to' remain in its lowestposition, which: could be the case were an operator s foot left on the foot portion 34 during Inas 3. A starting. device, comprising a bellf crank:

lever pivotally mounted for movement between' astarting position and a finish position; a gear segment mounted on the bell-crank lever for limited' movement relative: thereto and-for inter--- mittent' engagement with: a pinion; an'd' 'means gulding the movement of the gear segment rela'-- tive .to the bell crank lever, said segment haviiig v free and unencumberedslimited-movement=relative to. the bell crank lever except for thatcaused by contact with the guidingmeans-between a-first position adjacent the pinion and a second-position away from the pinion, theguiding meansbeing constructed to cause the segmentto" be the bell crank lever=ispivoted irom theifmi'sh";

position to the starting position.

4. A starting device, comprisingr abellficrank lever p-ivotally mounted-for movement betwe'en a starting position and a finish'position; arrarcue ate gear segment mounted on one arm ofsaid" lever for limited movement relative thereto and" means guiding the'movement of the gear segment relative to the bell crank lever, the gearsegment" having free and-unencumbered limitedmovement relative to' the bellcrank lever except forthat caused by contact with the guiding meansgthe.

guiding means being constructed to causathe segment to move inwardly relative to? said'arm when the lever is pivoted from thestartingposi' tion to the finish position, andoutwardl'y rela tive to said arm when the lever is pivoted from the finish position to the starting position.

5. A device of the type described, comprising a housing; a stop secured to said housing; a bell crank lever pivotally mounted on said housing for movement between a starting position and a finish position; and a gear segment mounted on one arm of said lever and having limited outward and inward radial movement relative thereto; means guiding the movement of the gear segment relative to said lever, said gear segment containing a projection for contact with the stop when the bell crank lever is in the starting position, the guiding means being constructed to maintain the gear segment in its extreme in- Ward position when the projection is in contact with the stop.

6. In a device of the type described, a housing; a pinion rotatably mounted on the housing; a bell crank lever pivotally mounted on the housing for movement between a starting position and a finish position; and an arcuate gear segment having teeth on the inner periphery thereof mounted on one arm of the bell crank lever for limited movement relative thereto; means guiding the movement of the gear segment relative to the lever, the gear segment having free and unencumbered limited movement relative to the lever except for that caused by con-tact with the guiding means, the guiding means being constructed to cause said segment to move inwardly into engagement with the pinion when the :bell crank lever is pivoted from the starting position to the finish position and outwardly away from the pinion when said lever is pivoted from the finish position to the starting position.

FRANK S. THOMAS, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,239,729 Shafer Sept. 11, 1917 2,004,431 Fitz Gerald June 11, 1935 2,109,281 Bosma Feb. 22, 1938 

